How to check if a column exists in a SQL Server table?
I need to add a specific column if it is does not exist. I have something like this, but it always returns false:
IF EXISTS(SELECT *
FROM INFORMATION_SCHEMA.COLUMNS
WHERE TABLE_NAME = 'myTableName'
AND COLUMN_NAME = 'myColumnName')
How can I check if a column exists in a table of SQL Server database?
SQL Server 2005 onwards:
IF EXISTS(SELECT 1 FROM sys.columns
WHERE Name = N'columnName'
AND Object_ID = Object_ID(N'schemaName.tableName'))
BEGIN
-- Column Exists
END
Martin Smith's version is shorter:
IF COL_LENGTH('schemaName.tableName', 'columnName') IS NOT NULL
BEGIN
-- Column Exists
END
A more concise version
IF COL_LENGTH('table_name','column_name') IS NULL
BEGIN
/*Column does not exist or caller does not have permission to view the object*/
END
The point about permissions on viewing metadata applies to all answers not just this one.
Note that the first parameter table name to COL_LENGTH can be in one, two, or three part name format as required.
An example referencing a table in a different database is
COL_LENGTH('AdventureWorks2012.HumanResources.Department','ModifiedDate')
One difference with this answer compared to using the metadata views is that metadata functions such as COL_LENGTH always only return data about committed changes irrespective of the isolation level in effect.
Tweak the below to suit your specific requirements:
if not exists (select
column_name
from
INFORMATION_SCHEMA.columns
where
table_name = 'MyTable'
and column_name = 'MyColumn')
alter table MyTable add MyColumn int
Edit to deal with edit to question : That should work - take a careful look over your code for stupid mistakes; are you querying INFORMATION_SCHEMA on the same database as your insert is being applied to for example? Do you have a typo in your table/column name in either statement?
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